Automatic air-brake mechanism for railroad-cars.



PATENTED SEPT. 13, 1904.

Y WQH. SAUVAGE. AUTOMATIC AIRBRAKE MEGHANISM PoR RAILROAD GARS.

APPLIOTIQN FILED NOV. 3, 1902. RENEWED JAN. 19. 1904.

N0 MODEL.

UNITED STATES Patented. September 13, 1904.

PATENT EEicE.-

WILLIAM H. SAUVAGE, OF NEW YORK, N. Y., ASSIGNOR OF FIFTY-ONETWO-HUNDREDTHS TO GEORGE E. KISSAM, OE NEW YORK, N. Y.

AUTOMATIC AIR-BRAKE NIECHANISM FOR RAILROAD-CARS.

SPECIFICATION formingpart of Letters Patent No. 769,839, dated September13, 1904.

Application led November 3, 1902. Renewed Ianuary 19, 1904. Serial No.189,757. (No model.)

To all whom, it 771/001/ concern.'

Beit known that I, WILLIAM H. SAUvAeE, a citizen of the United States ofAmerica, and a resident of New York city, county and State of New York,have invented certain new and useful Improvements in Automatic Air-BrakeMechanism for Railroad-Cars, of which the following is a specification.

This invention relates to air-brake systems of tlie general character ofthat shown and described in my pending application, Serial No. 189,756,filed January 19, 1904, to which reference may be had for a fullerexplanation than is necessary to be given herein.

The present improvement is designed more particularly for high speedtrains and for trains operating under conditions which require theapplication of considerable braking power in the outset and diminishedpower later.

The particular object in view is to provide for the automatic release ofthe auxiliary power, which is applied in the outset, and the decrease ofthe braking power as the speed of the train diminishes.

The nature and object of the invention will be more fully explainedhereinafter with reference to the accompanying drawings, in which-Figure 1 is partly a plan View and partly a horizontal section of myimproved brake apparatus unattached to a car. Eig. 2 is a detail in sideelevation. Fig. 3 is a vertical section of a valve for limitingadmission of compressed air to the auxiliary cylinder when auxiliarybraking power is not required.

The cylinder a represents the main brakecylinder of the ordinarycompressed-air brake subject to the control of the usual triple valve(not shown) through the pipe connection Z1.

c represents the main brake-lever, to which the rod d of the mainbrake-piston is connected, as usual, at e. f is the usual secondarybrake-lever, and g, 7L, and c' indicate connecting-rods of the usualbrake apparatus.

j represents the auxiliary brake-cylinder, and if: the piston thereoffor reinforcing the main brake-cylinder in the latter part of itsoperation by compressed air admitted thereto from the mainbrake-cylinder through the passage when uncovered by the mainbrakepiston (not shown) in the same manner as in my before-mentionedpending application.

The same automatic attaching and detaching device for connecting anddisconnecting the auxiliary piston-rod m and the main brakelever c, asshown in the said pending application, is also used herein-viz. thenotched end a of said rod, cam-slot 0, and the fixed stud-pin p-fordeflecting said notched end out of range of the brake-lever when retiredby the main brake-piston and returning said notched end into said rangewhen the brake-lever has nearly reached the limit of its forward strokein the normal application of the brake and just prior to the opening ofpassage Z by the main piston to apply the reinforcing effect on thegreater leverage after the brake-shoes have been applied tothe wheels bythe main brakelever with but slight movement of the auxiliarybrake-piston and corresponding economy of consumption of compressed air.Thus it will be seen that greatly-increased braking power is providedfor emergency cases-such, for instance, as a comparatively lightpassenger-train running at high speed or a heavy though slower freighttrain on a downgrade. Such excessive power is, however, liable to lockthe wheels and cause them to slide when, owing to reduction of speed ofthe train, the wheels have less torque opposing the holding power of thebrakes. The primary object of my present invention is therefore toprovide simple and effective means for automatically relaxing thisexcessive power as the train slows and the torque diminishes to avoidthe slipping of the wheels, and although various contrivances may beemployed for this purpose what I consider at the present time to be thepreferable form consists of a slight vent-orifice q, affordingrestricted escape of air from behind the auxiliary piston c and gradualreduction of the reinforcing power as the need of such power subsides.This vent may discharge directly into the atmosphere; but as it is thecustom for economizing air when in running down long grades with heavytrains the brakes are applied frequently, to

employ retaining-valves for retaininglimited pressure behind the pistoninstead of allowing full discharge I prefer to connect the vent into theusual retaining-valve train-pipe s for such retention when required,which is controlled by the usual retaining-valve t, which, as is wellknown, being set in one position by the handle u, effects such retentionand being set in another position allows free escape when retention isnot required.

Another object of my present yinvention is to control the automaticapplication of the reinforcing power within the limit of predeterminedpressure in the main brake-cylinder below which it is not desirable thatthe reinforcing power shall take effect, such pressure being sufficientfor normal operation of the brakes. For this purpose I provide acheckvalve o in the passagel from the main brakecylinder to theauxiliary brake-cylinder with means for normally closing said passageand to open it under pressure exceeding the predetermined limit andadapted to be adjusted for varying the opening pressure, such meansconsisting in this example of the coiled spring w, applied to the stem xof the valve and compressed between the back of the valve and theadjusting-plug y in the head a of the valvecase 2, and a cap 3, screwingon the upper end of the plug to close the case air-tight and for acheck-nut to secure the plug. I also provide a cut-out cock 4: in thepassage Z to cut out the auxiliary brake apparatus altogether when itmay be desirable to do so. It will be seen that with such automaticauxiliary brake-controlling valve the engineer may by hisbrake-operating valve in the cab govern the admission of compressed airinto the m'ain brake-cylinder and limit it below the pressure at whichthe valve e is set to open and insure non-action of the reinforcingpower when not wanted and when emergency requires he may by largeradmission so increase the pressure in the main cylinder as to open valveo and set the reinforcing power in action whenever required.

What I claim as my invention isl. In an air-brake, the combination withthe brake-lever and the main brake cylinder and piston, of an auxiliarybrake cylinder and piston, means for reinforcing the main brake cylinderand piston in the latter part of their stroke by the auxiliary cylinderand piston, and means for automatic gradual reduction of the power ofthe auxiliary cylinder and piston as the speed of the train diminishes.

2. In an air-brake, the combination with the brake-lever and the mainbrake cylinder and piston, of an auxiliary brake cylinder and piston,means for reinforcing the main brake cylinder and piston in the latterpart of their stroke by compressed air admitted into the auxiliarycylinder from the main cylinder, and means for automatic gradualreduction of the power of the auxiliary cylinder and piston as the speedof the train diminishes by restricted release of compressed air from theauxiliary cylinder.

3. In an air-brake, the combination with the brake-lever and the mainbrake cylinder and piston, of an auxiliary brake cylinder and piston,means for reinforcing the main brake cylinder and piston in the latterpart of their stroke by compressed air admitted into the auxiliarycylinder from the main cylinder by the main piston, and means for gagingthe pressure for such admission.`

4:. In an air-brake, the combination with the brake-lever and the mainbrake cylinder. and pistn, of the auxiliary brake cylinder and piston,means for reinforcing the main brake cylinder and piston in the latterpart of their stroke by compressed air admitted into the auxiliarycylinder from the main cylinder by the main piston, and means for gagingthe pressure for such admission consisting of the adjustable check-valvein the passage from the main brake-cylinder to the auxiliarybrakecylinder. Y

5. In an air-brake, the combination with the brake-lever and the mainbrake cylinder and piston, of an auxiliary brake cylinder and piston,means for reinforcing the main brakecylinder in the latter part of theirstroke by compressed air admitted into the auxiliary cylinder from themain cylinder, means for automatic gradual reduction of the power of theauxiliary cylinder and piston as the speed of the train diminishes andmeans for gaging the pressurefor admission of air from the mainbrake-cylinder to the auxiliary brakecylinder. f

Signed at New York this 1st day of Novembei,l 1902.

WILLIAM H. SAUVAGE. Witnesses: v

A. P. THAYER, C. SEDGWICK.

TOO

